Safety-crank for shafts.



W. LI MILLER.

SAFEYY CRANK FOR SHAFTS.

APPLICATION FILED IuIIE 9,19I5.

Patented July 4, 1916. t

fade/fora? WILLIAM I.. MILLER, or MADISON, Wisconsin, assienon "ro eIsriOL'r MACHINE f ooiuraiw, or MADISON, WISCONSIN, A CORPORATION or Wisconsin.-

sanary-enana Fon snarrs'.

Specification pf Letters Patent.

Patented July d, MMG..

Application led'lfune 9, 1915. Serial No. 33,025.

To all whom t may concern.'

Be it known that I, WILLIAM L. Minnen, a citizen of the United States, residing at Madison, in the county ofDane and State of Visconsin, have invented certain new and useful lmprovements in Safety-@ranks for Shafts, of which-the following is a speciication.

This invention relates to manual. shaftturning devices, and, in its principal intended application, has reference to a device in the nature of a safety crank for .application to the projecting ends of continuously revolving shafts when a manual turning of the shaft may be required. ln many types of lathes and other machinevtools shafts are employed which are in continuous rotation when the machine is in operation, but which are required'to be turned manually in setting up the machine. Hence, one or* both ends of such shafts are commonly projected through the wall or walls of the housing and are provided with a squared end for the application of a crank having a square socket in its hub to edect such manual turning of the shaft. 4 These square projecting shaft ends which are continuously revolving during the operation of the machine present an element of danger to the operatives in their liability to catch and wind up the clothing of the operative resulting 1n Vdamage to the clothing and sometimes injury to the operative.

rlhe object of my present invention is to provide a nntnually Operable device for effecting the turning of such shafts in setting up the machine; which shall entirely eliminate :the objectionable and dangerous character of such shafts as at present employed.

'lhe device of my invention, its mode of use, and the 4advantages attendant upon the same will all be readily understood from a consideration of the accompanying drawing taken in connection with .the following de tailed description.

ln the draWing-Figure Vil is an elevational view, partly in axial longitudinal seotion, of a. shaft end and shaft turning device therefore embodying my present invention; Fig. 2 is an axial longitudinal section through the hub portionV of the crank, the same being removed -from the socket of the shaft; F ig. 3 is an end elevation of the parts" shown in Fig. 2 as viewed from the left of the latter gure; E ig. 4 is an end elevation of the socketed end of the shaft; Fig.

rotating shaft so formed as'to be capable of adjustment by the same device that eects adjustments of rotating shafts.

'5 is an elevation view'of the end of a non- Referring to Figs. 1 to 4 of the drawing, I

' sides of the outer square portion 7, as clearly shown in Fig. 4. 9 designates the hub, 10 the arm, and 11 the handle of a manually operable crank for turning the shaft 5 in setting up the machine or whenever otherwise required. The hub 9 is formed with a squared portion 12, and, beyond the latter, with a round portion 13; these squared and round portions of the hub being adapted to a sliding fit in the squared and round por- -tions 7 and 8 of the shaft socket, respectively.. ,l f

Alt vis evident that ifa workman, having applied the crank and turned the shaft to the required extent, were to forget to remove the crank and leave the same in place, after the machine was started the revolving crank would be quite as dangerous as, or more soV than, a continuously revolving squared end. To safeguard against such a contingency l provide means for automatically disconnecting the crank from the socket of a revolving shaft as soon as the Workman releases his hold on the former, such means as lie-rein shown comprising a pin 14C slidaloly mounted in and axially of the hub 9, said hub having an axial bore 15 to accommodate said shaft and a pin-actuating spring 16. The pin 14 has a sliding bearing in a reduced portion 151 j of the bore 15 at one end of the hub and in a concentrically bored nut 17 tapped into the other end of the hub. The spring 16 is confined between the nut 17 and a collar or integral annular enlargement 18 of the pin 14:, said collar 18 in turn abutting against an annular shoulder 19 of the' reduced end wall of the hub. The normal tendency of the spring 15 therefore, isl to maintain the pin 14: in the position shown in Fig. 2.

When the crank is applied to the socketed end of the shaft 5, the projecting end of the pin 14 strikes the bottom of the socket, and

v as the hub of the crank is entered into the socket, the pin is compressed and the pin is forced in' the opposite direction relatively to the hub, as illustrated in Fig. 1. In turnin the crank a slight inward pressure (towar the shaft) on the part of the operative maintains the crank in operative engagement with the shaft; but the moment the crank is released the expansion of the spring 16,

cable thereto, l provide the shaft end formation illustrated in Fig. 5, wherein 5EL designates the end portion of a non-rotating. shaft, which is structurally identical with the end portion 5 of a rotating shaft, except that it is provided with a hole or socket 20 extending inwardly of thesquare and round crank-engaging sockets 7 and 8, to accom- Vmodate the projecting portion of the pin 14,

so that the crank, when applied to shaft 5a' will not be thrown ofi' automatically 4when the workman releases his hold thereon.

The rounoi portions of the socket and crank hub are not indispensable, but are preferably employed for the reason that the forward round portion of the hub facilitates the application of the crank to theA shaft, since such forward round portion can obviously be entered into the square outer portion of the socket at any angle at which the hub and crank arm may be presented f and when thus entered it is necessary only to turn the crank with a slight inward pressure until the squared portions come into registration with each other; the round por- 'within the socketed end of said shaft, and means operative to force said crank hub out v of engagement with said shaft when the crank is released. y

2. The combination with a shaft having in an end thereof a socket the inner portion of which 'is round andthe outer portion polygonal in cross-section, of a crank forturning said shafthaving a hub provided with a socket-engaging member the outer portion of which is round 'and the inner portion polygonal in cross-section to fit the inner and outer portions respectively of said socket.

3. The,combination'with a shaft having a centrally socketed end, of a crank for turning the same having a hub providedoyith a rigid portion non-rotatably'fitting within `the socketed end of said shaft, and springactuated means within said hub operative to disengagethe latter from said shaft when the crank is released.

4f. The combination with a shafthaving A in an end thereof a socket the inner portion of which is round and the .outer portion polygonal in cross-section, of a crank for turning said shaft having a hub provided with a socket-engaging member the outer portion of which is round and the inner por` tion polygonal in cross-section to fit the inner and outer portions respectively of said socket, and a spring-actuated rod slidably mounted in said hub and adapted through engagement with the bottom of said socket to 'tend to force the socket-engaging portions ofv said hub 'out of engagement with said socket.

WILLXAM L. MLLER. 

